Some years ago a business in our same building closed shop. They were a Title Company and they had lots of cool office supplies they let us take. Among fancy semi-transparent Post-It notes and other goodies I picked up a packet of red pens. “These will be great for red-marking contracts, resumes and things like that,” I thought.
Later I discovered the red pens issued… royal blue ink. Uh?
I kept these pens with me—unused—as an example of an incongruent user experience.
In user interfaces, be mindful of the same principle. Aid users by offering “red pens” that deliver red ink. For example, do not just use buttons that says “Yes” or “No” to confirm a deletion. Instead say “Delete”. Red Ink.